The Project Data includes information from sites in England, Wales, Scotland and beyond. The bulk of the data is from sites in England from where the greatest amount of information for the period has been forthcoming in Britain. Including data from Wales and Scotland within a survey funded by English Heritage is appropriate given the considerable potential for comparative analysis, as both areas have yielded exceptionally significant well-dated samian groups. Further, of course, the modern political units are not those of the Roman era when England, Wales and periodically parts of Scotland were within the empire as one province. Nonetheless, of course, both Wales and Scotland approximated to distinct geo-cultural regions at that time.
Both Wales and Scotland have closely dated Roman military horizons that are significant in examining chronological trends and other patterns in terms of samian data, while the assemblages from indigenous and other non-military sites in these areas are also more than noteworthy. Project work and results benefit from the inclusion of some data from these regions within the analyses. Evidence from sites in both Wales and Scotland was referenced in the paper published in The Archaeological Journal (Willis 1998a).
Samples recorded from Welsh and Scottish sites has aimed to include a variety of types of site, including those of indigenous association, not simply military assemblages. Work undertaken as part of Phase 1 of the Project, however, established that there are attendant aspects of the nature of the evidence from these regions and the manner in which it has been reported, which mean that the use of this material is not always straight-forward. Assessment of the published samian information from sites in Wales indicates clearly that the samian from these sites has, with very few exceptions, not been presented in publications (nor recorded) in either a full and or quantitative manner. The nature of the recording and publication of most samian assemblages in Wales therefore means it, regrettably, cannot be used for the database, nor for most other analyses, including simple comparative methods. Peter Webster (University of Wales, Cardiff) has been collating samian and other Roman pottery information from military sites in Wales as part of a survey funded by the Board of Celtic Studies. Some of the data collected in his research may prove to be compatible with the methodology used for this Project, but in sum the possibilities for referencing samian data from sites in Wales have been limited.
Assessment of the published samian information from sites in Scotland provides a contrasting picture to that of Wales. A series of readily accessible (published) samian lists from excavated sites were available, from both military sites and indigenous centres, in a format suitable to the methodology of this Project. An amount of quantified data were also available. Samian from military horizons in Scotland (Flavian to early Trajanic, and Antonine) represent episodes of occupation that were comparatively short lived. Such groups are significant from a chronological viewpoint as they are closely-dated. There may, however, be thought to be a potentially distorting factor in so far as they seem likely to be composed largely from direct 'fresh' supplies, whereas, for instance, contemporary civilian sites occupied over a long period will have, at any one time, a carry-over of vessels from previous years that were still in use. This is, however, a general pattern with military sites across Britain.